Reasons for high outlet temperature of the adsorption dryer
The high outlet temperature of the adsorption dryer may be caused by excessive inlet air temperature, accumulation of adsorbents, prolonged drying time, or uneven heat distribution. Reasonable adjustments can improve efficiency and reduce losses.
As the core equipment for post-treatment of compressed air, the adsorption dryer’s main function is to adsorb moisture from the air using adsorbents (such as molecular sieves, activated alumina), and output low dew-point dry air. The analysis of the reasons for the excessively high outlet temperature of the adsorption dryer:
1. It is necessary to observe the normal temperature fluctuations (understand the principle)
First, it is important to understand that the outlet temperature of the adsorption dryer is not constant and will fluctuate regularly within one regeneration cycle:
● Adsorption process: When compressed air flows through the adsorbent (such as alumina, molecular sieve), water vapor is adsorbed and releases adsorption heat. This part of the heat causes the outlet temperature to slightly increase in the initial stage of adsorption.
● Regeneration process: In another tower, this tower is in the adsorption state, and the outlet temperature will gradually drop.
● Instantaneous switching: When the two towers switch, the hot tower that has just completed regeneration (with a high temperature) starts to adsorb, and a large amount of heat is carried out by the process air, resulting in a temporary peak in the outlet temperature. This is a normal phenomenon, and usually high-performance dryers will reduce this peak through “pressure equalization” and other operations.
● Conclusion: If the temperature only fluctuates within a small range periodically, it is normal. However, if the overall temperature is consistently high or the peak is abnormally high, the following issues need to be investigated.
2. Abnormal cause analysis
1. Excessive inlet air temperature is the most common reason, which will cause the outlet temperature to rise.
Solution: Use cooling methods or other technical means to keep the inlet air temperature within the appropriate range.
2. After the adsorption dryer has been operating for a period of time, the adsorbents will accumulate inside the dryer. This will cause the internal temperature of the dryer to heat up, resulting in an increase in the outlet temperature.
Solution: Regularly clean the adsorbents to avoid excessive accumulation.
3. Excessive drying time will cause the internal temperature of the dryer to rise, resulting in an increase in the outlet temperature.
Solution: Adjust the drying time to keep it within the appropriate range.
4. If the heat distribution is unbalanced during the operation of the adsorption dryer, it will cause uneven temperature, resulting in an increase in the outlet temperature.
Solution: Based on the characteristics of the drying material and the heat requirements, make a reasonable heat distribution.
The above are the reasons for the high outlet temperature of the adsorption dryer and the solutions. If these methods can be reasonably applied to solve the problem, it can effectively improve production efficiency, reduce equipment losses, and ultimately help enterprises achieve better economic returns.
